1. Field of the Invention:
This invention relates to weighing devices and more particularly to a portable device which may be conveniently stored when not in use and then readily assembled into an accurate weighing instrument.
2. Prior Art:
Weight devices are well known and have been in use for thousands of years. Many such devices utilize the mechanical principle of balancing a clockwise and a counterclockwise moment of force about a pivot point. In each case the magnitude of the force moment is equal to the product of the force and the distance that the force is from the pivot point. Balancing occurs when the force moments have equal value. The structure of a particular device depends generally on whether the force and/or distance comprising a moment is fixed or may vary.
In one known weighing device, sometimes referred to as a weighing scale, weighing pans are carried respectively from ends of an arm and spaced an equal distance on each side of a pivot supporting the arm. The object to be weighed is placed in one pan while pieces of metal each having a specific known weight, i.e. weights, are placed in the other pan. Weights are selectively added until the pans balance. The weight of the object is equal to the sum of the numerical values of the weight pieces.
Another well known weighing device often found, for example, in doctors' offices and in post offices, comprises a support plate operatively connected to one end of a pivot arm. On an opposite side of the point where the arm is pivotally supported is a slidable weight. After the object to be weighed is placed on the support plate, the position of the weight is adjusted until the arm balances in a horizontal position. The weight of the object is equal to the position of the weight with respect to numerical weight values on a scale on the arm.
A still further known weighing device includes a spring operatively connected to a fitting to which an object to be weighed may be attached. The object compresses the spring to selectively position an end of the spring along a scale on the device. The weight of the object is equal to position of the spring end with respect to numerical values on the scale. Weighing devices incorporating this structure are presently available for sport fisherman use. Such devices, while not particularly accurate, are compact and may be readily stored when not being used.